Teydealdehyde, a C23-terpenoid from transformed root cultures of Nepeta teydea

Teydealdehyde, a C23-terpenoid with a new carbon skeleton, has been isolated from Nepeta teydea root cultures transformed by Agrobacterium rhizogenes. Its structure, determined from HRMS, 1D and 2D NMR data, shows four cycles with a five membered A ring deoxygenated at C-3 and with a C-2 aldehyde group at C-1. The B-, C- and D-rings are similar to those of the oleanane, ursane and lupane triterpenes, but the last cycle contains an α,β-unsaturated ketone as the result of a ring E biodegradation process of a pentacyclic triterpene precursor.